Rhizopus head rot. Rhizopus Head Rot Introduction. ... Abstract. The objective of this study was to determine the effects of head rot disease on seed yield in eight sunflower cultivars. Wet weather following flowering is conducive to Rhizopus head rot. Head rot caused by Rhizopus stolonifer reduces sunflower seed yield and quality. While both are widely distributed, white mold is a more serious problem in northern production areas, such as North Dakota, South Dakota, and Minnesota. These species may occur singly or in a Rhizopus head rot is a common and often severe fungal disease of sunflowers primarily in the high plains of the USA. This 2007 NebGuide discusses the pathogen, disease history, symptoms, and management. Authors. In the United States, Rhizopus head rot has historically caused only minor and localized damage to sunflowers. Rhizopus head rot has been reported from several areas of sunflower production in the world, including Australia, South Africa, and Mediterranean areas in Europe and India. Plants are virtually immune to infection at Rhizopus Head Rot. The results revealed that Sclerotinia sclerotiorum. Rhizopus head rot is caused by various fungi in the genus Rhizopus, including R. arrhizus, R. stolonifer, and R. microsporus. The disease is common on … Download DOWNLOADS. Rust Puccinia helianthi Puccinia xanthii Uromyces junci. Rhizopus head rot Rhizopus arrhizus = Rhizopus nodosus Rhizopus microsporus Rhizopus stolonifer = Rhizopus nigricans. R. stolonifer, R. oryzae (syn. The affected heads turn brown and mushy, and then brittle and hard as they dry out. Sclerotinia head rot. head rot, and Rhizopus head rot. Rhizopus head rot is caused by various fungi in the genus Rhizopus, including R. arrhizus, R. stolonifer, and R. microsporus. The Rhizopus head rot pathogens require free moisture and a wound to successfully infect sunflower heads. Sunflower crops grown in Nebraska are susceptible to diseases caused by bacteria, viruses and nematodes, but the most economically damaging is head rot, caused by the fungal pathogen Rhizopus. The Rhizopus head rot pathogens require free moisture and a wound to successfully infect sunflower heads. Since June 17, 2009. This NebFact discusses the increase in sunflower production and the potential for diseases. 2000. Rhizopus Head Rot of Sunflower in Nebraska G1677 Sunflower crops grown in Nebraska are susceptible to diseases caused by bacteria, viruses, and nematodes, but the most economically damaging is head rot, caused by the fungal pathogen Rhizopus. Date of this Version. Rhizopus head rot is more serious in southern sunflower production regions including Kansas, Nebraska, Colorado, and the Texas Panhandle. The sunflower cultivars were inoculated by R. stolonifer at two different growth stages (R5.7 and R6.0) of sunflower. Robert M. Harveson, University of Nebraska--Lincoln Follow. These fungi are cosmopolitan in soil and decaying organic matter. Head rot, caused by one or more species of Rhizopus, occurs sporadically, causing rotting and shredding of the head similar to Sclerotinia head rot. FIGURE 4 – White mycelium and black sclerotia on the face of a skeletonized sunflower head. Sclerotinia basal stalk rot and wilt, mid-stalk rot, head rot Sclerotinia sclerotiorum = Sclerotinia libertiana = Whetzelinia sclerotiorum. NF00-426 Rhizopus Head Rot of Sunflower. Included in. These fungi are cosmopolitan in soil and decaying organic matter. Head rot disease is caused by several species in the genus Rhizopus, including R. stolonifer, R. arrhizus, R. oryzae, and R. microsporus. AUTHORS: Sam Markell, Tom Gulya, Charlie Block and Bob Harveson. 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